As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ESTABLISHED ON FINAL, FULLY CONFIGURED AT THE FINAL APPROACH FIX, THE FLIGHT DIRECTOR SWITCHED OVER TO B/C MODE & PITCH MODE. THE AIRCRAFT TURNED 15° TO THE RIGHT. PILOT DISCONNECTED THE AUTO PILOT AND FLEW THE REST OF THE APPROACH. (FLT 4474) PERFORMED FCC DIAGNOSTIC ON MDC, NO FAULTS FOUND. PERFORMED OPS CHECK OF AUTO PILOT SYSTEM IAW AMM. NO DISCREPANCIES NOTED.